diff options
Diffstat (limited to 'nscd/nscd_helper.c')
| -rw-r--r-- | nscd/nscd_helper.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/nscd/nscd_helper.c b/nscd/nscd_helper.c index 5f3d54efcf..6718d922f3 100644 --- a/nscd/nscd_helper.c +++ b/nscd/nscd_helper.c @@ -416,7 +416,10 @@ __nscd_cache_search (request_type type, const char *key, size_t keylen, unsigned long int hash = __nis_hash (key, keylen) % mapped->head->module; size_t datasize = mapped->datasize; - ref_t work = mapped->head->array[hash]; + ref_t trail = mapped->head->array[hash]; + ref_t work = trail; + int tick = 0; + while (work != ENDREF && work + sizeof (struct hashentry) <= datasize) { struct hashentry *here = (struct hashentry *) (mapped->data + work); @@ -454,6 +457,23 @@ __nscd_cache_search (request_type type, const char *key, size_t keylen, } work = here->next; + /* Prevent endless loops. This should never happen but perhaps + the database got corrupted, accidentally or deliberately. */ + if (work == trail) + break; + if (tick) + { + struct hashentry *trailelem; + trailelem = (struct hashentry *) (mapped->data + trail); + +#ifndef _STRING_ARCH_unaligned + /* We have to redo the checks. Maybe the data changed. */ + if ((uintptr_t) trailelem & (__alignof__ (*trailelem) - 1)) + return NULL; +#endif + trail = trailelem->next; + } + tick = 1 - tick; } return NULL; |